Insecticide formulations



Imam 1. a J w INSECTICIDE FORMULATIONS Leo Trademan, Marshall A. Malina, and Louis P. Wilks,

Chicago, Ill., assignors to Velsicol Chemical Corporation, a corporation of Illinois No Drawing. Application October 7, 1954 l Serial No. 461,036

4 Claims. o1. 167-30) This invention relates tdinsecticide compositions and to methods of stabilizing them. More particularly, the present invention relates to dry formulations of certain halogenated insecticides stabilized with organic compounds containing two hydroxyl groups.

Dry formulations of halogenated insecticides fall into {three main classifications, namely dusts, wettable powders 'and granular formulations. Dusts and granular formulations differ primarily in particlesize of the carrier. ordiluent used. For example, a typical dust formulation may comprise an insecticide dispersed in a solid carrier having a particle size smaller than about 325 mesh. A typical granular formulation would comprise an insecticide dispersed in a solid carrier having. a. particle size of about 20-80 mesh. A typical wettable powder comprises an insecticide and a solid carrier having a particle size of the order of that used for dust formulations, in conjunction with wetting and dispersing agents.

Typically, a granular formulation may contain from about 2% to about 35% insecticide by weight. This type of formulation is generally used as such without further dilution with an insecticidally inert carrier in such fields as agriculture.

Typically, a dust formulation can contain about 0.25%

tion of toxicant on the order of that contained indust concentrates as above described. However, they are diluted to field strength by dispersing in water rather than by dispersing in dust. a p p u The toxicant ingredient of the dry insecticide formulations which is stabilized by the present invention" is selected from that class of insecttoxicants which are derived from hexachlorocyclopentadiene and which are specifically typified bychlordane, heptachlor,' aldrin, iso

drin, dieldrin or endrin, eitherinfltheir pure or technical form. u The carriers ordiluents generally used with these insect toxicants, and which in theit normal state are active in deteriorating the aforesaid class of toxlcants when mixed therewith-without treatinentas specified in the-[present invention, are solids of theclass consistingbf'kaolin clays, montmorillonite clays, attapulgite claysydiatornaceous earths andvermiculites. u I i Kaolins such as kaolinite, dickite, nac'rite, anauxite,

halloysite and endellite are useful as carrier materials. Montmorillonites, such as beidellite, nontronite, montmorillonite, hectorite, ,sap'onite, sauconite and benton'ite are useful as carrier materials Attapulgites such as 2,875 ,1 l9 Patented Feb. 24, 1959 and kieselguhr are useful as carrier materials. Vermiculites such as biotite are useful as carrier materials.

Having now described the types of formulations herein concerned, the insect toxicants employed, and the carriers and diluents used, a brief discussion of the problem encountered in such formulations will be helpful in understanding the present invention.

While the solid carriers above discussed are very useful in formulating the herein defined toxicants for reasons of theirinexpensiveness, availability, ease of handling,

absorbency characteristics,durability and other desirable physical properties, they have the disadvantageous property, to varying degrees, of degrading or decomposing the insect toxicant when intimately mixed therewith. While this degrading action is a slow process, it is significant and troublesome since dry formulations are often prepared as concentrates or even field strength materials and then stored for periods which may be as long as a year or more. During this storage period the effect of the carrier or diluent on the insect toxicant ingredient may reduce its effectiveness to the point where satisfactory insect control under field conditions is no longer obtainable.

The nature of the reaction or effect of the carriers on the chlorinated insecticide has never been fully elucidated. The rate of toxicant deterioration may vary by the action of different carriers or diluents. v

Tohsolve the present problem it has been found necessary to neutralize the activity of the solid carriers and diluents so that they are inert to the insect toxicant and will allow protracted storage of dry insecticide formula- Itions without deterioration of insecticidal activity of such ponderantly in agriculture, any treatment of the carriers and diluents usedmust necessarily not render the formulation unfit for agricultural use on food and forage corps ,at time of harvest. Thus, the treatment must not render the formulation phytotoxic. The treatment must likewise not be hazardous from a warm-blooded animal toxicity standpoint, or otherwise increase the hazard in the utilization of insecticide formulations. Also, of primary importance, and considering the economics involved, the

treatment must not involve expensive materials, nor can the process of treatment be complex. Another consideration in the present problemis that the treatment must not affect the insecticidal activity of the toxicant employed,

It is therefore an object of the present invention to provide an additive to dry insecticide formulations which will prevent deterioration of the insect toxicant ingredient during storage.

It is another object of the present invention to provide an additive to dry insecticide formulations, for the purpose of stabilizing them, which is neither acidic nor basic,and which is relatively nontoxic.

It is another object of the present invention to provide an additive to dry insecticide formulations, for the purpose of stabilizing them, which is not deleterious to plant life.

and by use of readily available ingredients.

- It has now been discovered that the solid carriers and .diluents which were previously described and which are active in deteriorating the class of insecticides herein conearned can be rendered substantially inert by the addition :thereto of a small quantity of glycol material selected from the class ethylene glycol, diethylene glycol, propylene glycol and triethylene glycol. a a y fullers earth, attapulgite and sepiolite are useful as" carrier materials. Diatomaceous earths such as diatomite It' is surprising and unexpected that these materials sould be aszelfective as they are, since they. are neutra insofar as pH is concerned and their stabilizing effect in 12%. by weight based on the weight of carrier or diluent contained in the formulation. A preferred concentration of glycol additive to dry insecticide formulations is about 2% to about 8% by weight based on the weight of carrier or diluent. i

The art of blending materials with solid carriers and diluents of the class herein described is'well known, and the liquid additives of the present invention can be blended with these solid materials by any known means. For example, the use of commercial type mixers or blenders is adequate. The present glycols can be added to and blended with the solid carriers either alone or in combination with an inert, relatively volatile solvent which can be removed after blending.

The glycol additives can be added to the solid carriers prior to blending the insect toxicant therewith. In the alternative, the glycol additives can be added to the solid carriers during the same blending operation wherein mixing of the insect toxicant and carrier is achieved. It s p e e d t r l he co additi e Q h carrier before blending the insect toxicant.

The following specific information exemplifies the beneficial effect of the present glycol additives using triethylene glycol as representative of the glycols herein disclosed; using a kaolin and an attapulgite dust of size to pass through a 325 mesh screen as representative of the solid carriers; and endrin of 98% purityas representative of the insect toxicant.

Triethylene glycol (3 wt. percent based on Weight of clay) was blended with Barden Clay (a trade name for a kaolin) by mixing and blending for 10 minutes in a standard dry blender. The thus impregnated kaolin dust was then used as a carrier to prepare a 20% endrin concentrate. This was accomplished by standard blending technique. The resulting 20% concentrate was further diluted with triethylene glycol treated kaolin to a formulation containing 2% endrin. .lfhe final formulation had the following composition:

2.94 wt. percent triethylene glycol 95.06 Wt. percent Barden Clay (kaolin) 2 wt. percent endrin Another 2% endrin formulation having the following composition was prepared using the same Barden Clay (kaolin) without treating it with triethylene glycol:

98 wt. percent Barden Clay (kaolin) 2 wt. percent endrin i These'two formulations were then subjected to accelerated storage tests in an oven maintained at 122 F.

Formulation Formulation A, weight B, weight percent percent Emil-in 2 2 Attapulgite (325 mesh) 90. 16 98 'lriethyleneglycol 7. 84

Formulations A and B were subjected to accelerated aging tests in an oven maintained at 122 F. After 24 hours, the concentration of endrin in formulation B was determined by infrared analysis tobe 0.46%; whereas after 30 days of accelerated aging, the concentration of endrin in formulation A was unchanged.

The following tables indicate the stabilizing effect of diethylene glycol in varying concentrations on attapulgite and kaolin dusts when such carriers are used to formulate technical heptachlor:

Table I Wt. Wt. Percent Wt. Percent Carrier Percent Diethylene Dust-325 Mesh Technical Glycol Heptachlor 82.74 (Attaclay) Formulation L. 11 Formulation II. 86.33 (Barden Clay)... 11 Formulation III (Attaclay) 25 (Barden Clay) l0 Formulation IV- Table 11 Days Subjected to Accelerated Storage at 122 F.

10 Days 30 Days 60 Days 7 Concentration of Technical Heptachlor in V WtjPercent of Total Formulation 1 Unchanged..-

FormulationI Unchanged Unchanged. Formulation II Unchanged")- Unchanged Unchanged. Formulation III 19.9 17.9".-. 13.8. Formulation IV 4.2 4;0

metrically.-

It is evident from a review of Tables I and II that the use of 3% of 7% diethylene glycol based on weight of the carrier is effective in eliminating decomposition "of technical .heptachlor formulated with attapulgite and The technical heptachlor concentration was determined spectrophotokaolin respectively. The untreated formulations (III and regardless of the particle size thereof or formulation type,

su'eh as whether they be in a dust form, Wettablepowder form'or granular form.

Also, as previously stated, these glycols are useful in stabilizing dry formulations of the class dusts, wettable pow ers "a dT' nmar form la on f those r y lorinated .insect 'toxicants derived from hexachlo'rocyclonsnt dis eand t p fie b en r n i n d r n heptash t e tl'chlq' ds i We claim:

1, stabilised insecticidal composition comprising in ,con bination; an insecttoxicant derived from hexachlorocyclopenta ene selected from the group'consi'sting of endrin, i in, aldrin, dieldrin, chlordane and heptachlor; ed solid earrieractive in deteriorating said inseettoxiciul mixed therewith selected from the group consisting of kaolin clay, montmorillonite clay, attapulgite clay, diatomaceous earth and vermiculite; and between V2. and 12% by weight of the carrier of a glycol which alleviates said deterioration of the insect toxicant selected from the group consisting of ethylene glycol, propylene glycol, diethylene glycol and triethylene glycol.

2. A stabilized insecticidal composition comprising in combination: heptachlor; a finely divided solid carrier active in deteriorating said insect toxicant mixed therewith selected from the group consisting of kaolin clay, montmorillonite clay, attapulgite clay, diatomaceous earth and vermiculite; and. a glycol which alleviates said deteri oration of the insect toxicant selected from the group consisting of ethylene glycol, propylene glycol, diethylene glycol and triethylene glycol.

3. A stabilized insecticidal composition comprising in combination: endrin; a finely divided solid carrier active in deteriorating said insect toxicant mixed therewith selected from the group consisting of kaolin clay, montmorillonite clay, attapulgite clay, diatornaceous earth and vermiculite; and between /2% and 12% by weight of the carrier of a glycol which alleviates said deterioration of the insect toxicant selected from the group consisting of ethylene glycol, propylene glycol, diethylene glycol and triethylene glycol.

4. A stabilized insecticidal composition comprising in References Cited in the file of this patent UNITED STATES PATENTS 2,371,644 Petering Mar. 20, 1945 2,407,149 Gardenier Sept. 3, 1946 2,657,165 Buntin Oct. 27, 1953 2,722,557 Danison Nov. 1, 1955 FOREIGN PATENTS 708,116

Great Britain Apr. 28, 1954 OTHER REFERENCES Watkins: Handbook of Insecticide Dust Diluents and Carriers, Dorland Books (1955), pp. 161-200, 136-160, 200-214, -70 and 96-100.

Roark: U. S. Dept. Agri., Publ. E-817 (1951), p. 11.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No, 2,875,119 February 24, 1959 Leo Trademan et al It is hereby certified that error appears in the -printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 1, line 41, for typical" read we typically; column 2, line 36, for "corps" read crops line '71, for "soulci" read should column 4, line 46, for "3% of 7%" read 3% and 7% column 5, line 12, before "a glycol" insert between l/2% and 12% by weight of the carrier of Signed and sealed this 9th day of February 1960.,

(SEAL) Attest:

KARL AXLINE ROBERT c. WATSON Attesting Officer I Commissioner of Patents 

1. A STABILIZED INSECTICADAL COMPOSITION COMPRISING IN COMBINATION: AN INSECT TOXICANT DERIVED FROM HEXACHLORO CYCLOPENTADIENE SELECTION FROM THE GROUP CONSISTING OF ENDRIN, ISODRIN, ALDRIN, DIEDRIN, CHLORDANE AND HEPTACHLOR; A FINELY DIVIDED SOLID CARRIER ACTIVE IN DETERIORATING SAID INSECT TOXICANT MIXED MIXED THEREWITH SELECTED FROM THE GROUP CONSISTING OF KAOLIN CLAY, MONTMORILLONITE CLAY, ATTAPULGITE CLAY DIATOMACEOUS EARTH AND VERMICLITE; AND BETWEEN 1/2% AND 12% BY WEIGHT OF THE CARRIER OF A GLYCOL WHICH ALLEVIATED SAID DETERIORATION OF THE INSERT TOXICANT SELECTED FROM THE GROUP CONSISTING OF ETHYLENE GLYCOL, PROPYLENE GLYCOL, DIETHYLENE GLYCOL AND TRIETHYLENE GLYCOL. 